Signal transmission circuit

Abstract

A clock generation circuit 10 includes a resonant reactor connected with a half voltage supply point TV 1 , a resonant capacitor CL connected between a ground voltage supply point TVss and an output terminal TVout, a transistor MPconnected between the resonant reactor Lr and the resonant capacitor CL, and a transistor MN 1 connected with the output terminal TVout. In this configuration, signals in a wide range of frequencies can be output with low power consumption by adjusting the time when a clock signal φ1 applied to the gates of the transistors MP 1 and MN 1 is high.

What is claimed is: 
     
       1. A signal transmission circuit, comprising:
 a resonant reactor connected with a first voltage supply point, which a first voltage is supplied to; 
 a resonant capacitor connected between a second voltage supply point, which a second voltage is supplied to, and an output terminal; 
 a first switching element connected between the resonant reactor and the output terminal and configured to be turned on and off by a first switching signal; and 
 a second switching element connected between the output terminal and the second voltage supply point and configured to be turned on and off by a second switching signal, 
 wherein the first switching signal and the second switching signal are respectively control signals configured to periodically turn on and off the first switching element and the second switching element with elapse of time, 
 the signal transmission circuit further comprising a timing adjustment circuit configured to store a previous voltage that is a voltage of a signal output from the output terminal in a last cycle, compare the previous voltage with a voltage of a signal output from the output terminal in a current cycle and adjust a timing of transition of the first switching signal and a timing of transition of the second switching signal, based on a result of comparison. 
 
     
     
       2. The signal transmission circuit according to  claim 1 , wherein
 the timing adjustment circuit comprises: 
 a first adjustment capacitor connected with the second voltage supply point; 
 a second adjustment capacitor connected with the second voltage supply point; 
 a changeover switch configured to switch between a connection of the output terminal with the first adjustment capacitor and a connection of the output terminal with the second adjustment capacitor, by a first adjustment switching signal; 
 a comparator circuit configured to compare a voltage of the first adjustment capacitor with a voltage of the second adjustment capacitor at a rise timing or a fall timing of a second adjustment switching signal and output a result of comparison; and 
 a clock signal supply circuit configured to input a clock signal, adjust a pulse width of the input clock signal based on the result of comparison by the comparator circuit, supply the clock signal of the adjusted pulse width as the first switching signal to the first switching element, supply the clock signal of the adjusted pulse width as the second switching signal to the second switching element, supply the clock signal of the adjusted pulse width as the first adjustment switching signal to the changeover switch and supply the clock signal of the adjusted pulse width as the second adjustment switching signal to the comparator circuit. 
 
     
     
       3. The signal transmission circuit according to  claim 1 , wherein
 the first voltage is a voltage higher than the second voltage. 
 
     
     
       4. The signal transmission circuit according to  claim 1 , further comprising:
 a third switching element connected between a third voltage supply point, which a third voltage is supplied to, and the output terminal and configured to be turned on and off by a third switching signal. 
 
     
     
       5. The signal transmission circuit according to  claim 4 , wherein
 the first switching signal, the second switching signal and the third switching signal are respectively control signals configured to periodically turn on and off the first switching element, the second switching element and the third switching element with elapse of time. 
 
     
     
       6. A signal transmission circuit, comprising:
 a resonant reactor connected with a first voltage supply point, which a first voltage is supplied to; 
 a resonant capacitor connected between a second voltage supply point, which a second voltage is supplied to, and an output terminal; 
 a first switching element connected between the resonant reactor and the output terminal and configured to be turned on and off by a first switching signal; 
 a second switching element connected between the output terminal and the second voltage supply point and configured to be turned on and off by a second switching signal; 
 a third switching element connected between a third voltage supply point, which a third voltage is supplied to, and the output terminal and configured to be turned on and off by a third switching signal, 
 wherein the first switching signal, the second switching signal and the third switching signal are respectively control signals configured to periodically turn on and off the first switching element, the second switching element and the third switching element with elapse of time, 
 the signal transmission circuit further comprising a timing adjustment circuit configured to store a previous voltage that is a voltage of a signal output from the output terminal in a last cycle, compare the previous voltage with a voltage of a signal output from the output terminal in a current cycle and adjust a timing of transition of the first switching signal, a timing of transition of the second switching signal and a timing of transition of the third switching signal, based on a result of comparison. 
 
     
     
       7. The signal transmission circuit according to  claim 4 , wherein
 the first voltage is a voltage higher than the second voltage but lower than the third voltage.